With development of communications technologies, requirements on function and performance of communications systems are becoming higher. An optical chip implements optical-to-electric signal conversion and electric-to-optical signal conversion, and an optical fiber implements low-loss and long-distance transmission. Optical signal transmission between different optical chips or between an optical chip and an optical fiber requires use of a complex optical coupling structure. Therefore, the optical chip is a key technology for development of optical communications, and an optical coupling technology of the optical chip is one of the bottlenecks that restricts development of an optical chip technology.
Some requirements on optical chip coupling include: (1) compatibility between “chip-optical fiber” coupling and “chip-chip” coupling; (2) compatibility between coupling manners such as an Edge coupler (EC), a Grating Coupler (GC), and an Adiabatic Coupler (AC); (3) high density: a single optical fiber connector includes not less than 84 channels, and density is not less than 5.25 channels/mm2; (4) single-mode or multi-mode signal transmission; and (5) a capability of implementing automatic, efficient, and high-precision optical encapsulation, and reducing an optical signal insertion loss.
In the prior art, none of a “Pitch Reducing Optical Fiber Array (PROFA)” solution used by Chiral Inc., an “optical PIN” solution proposed by the Photonics Electronics Technology Research Association (PETRA), a “polymer optical waveguide plate” solution used by IBM, a “Photonics Wire Bonding (PWB)” solution proposed by the Karlsruhe Institute of Technology (KIT), or the like can completely satisfy the above noted requirements on the optical chip coupling, and in particular, can satisfy compatibility between a plurality of coupling manners.